Method of making annealing-boxes.



L. L. KNOX- METHOD OF MAKING ANNEALING BOXES.

APPLICATION FILED MAR. 4, l9l6.

Patented June 13, 1916.

2 SHEETSSHEET 1- flWZNwESSES Patented June '13, 1916.

2 SHEETS-SHEET 2.

INVENTOR L.L-. KNOX. METHOD OF MAKING ANNEALING BOXES.

APPLICATION FILED MAR- 4. I916 WITNESSES 1 UN TED STATES PATEN OFFICE LUTHER L. KNoX, or AvAnoN, PENNSYLVANIA, nssreNon To KNox r nnssnn QWELDED STEEL COMPANY; or PITTSBURGH, PENNSYLVANIA, A CORPORATION;

OF PENNSYLVANIA.

: 7 METHOD" OFIIMAKING ANNEALING-BOXES.

Original applicationfiled April 17, 1915, Serial No. 22,079. Divided and" thisapplicationfi1ed-March 4, I Y 1916. Serial No. 82,193. I

To allwhom it may concern:

Be it known that I, LUTHER L. KNOX, a citizen of the United States, residing at Avalon, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Method of Making Annealing- Boxes, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming part of this specification, in which Figurel is a top planview, partly broken away, of an annealing box constructed in accordance wlth my invention. Fig. 2 1sa front elevation. Fig. S'is a transverse sec- 7 ,may be shaped in one integral piece without joints or seams, from a sheet metal blank. Also to' provide a method of this character in which provision is made in a novel manner for expansion and contraction movements, and for taking care, in a beneficial way, of excess metal resulting from the forming operations.

The present invention is a division of my pending application Serial No. 22,079, filed April 17, 1915.

In the accompanying drawings, in which I have shown the preferred form of box embodying my invention, the numeral 2 designates the body of the box which is open at the bottom, and 3 the integral arched top. The box is, in general, of the usual oblong form, but is provided at each of its corner portions with an outward swell or bend 4, extending beyond the general planes of the sides and ends of the box.

5 designates lifting lugs which are secured preferably by welding to opposite sides of the box.

The box is made from a single integral sheet of metal by successive drawing opera tions. I preferably 'start with a blank 6 of the general form shown in Fig. 4. In the first drawing or shaping step, the box is given the general oval shallow form indi- I cated at 7 in dotted lines in Figs. 4 and '5.

In then'e'xt forming step,mit is given the deeper and generally oblong rectangular form shown at "8, in said figures. In the next step, the sides and endsof the box are compressed, and the outwardly bulged corner portions 4 are formed.

It will be noted by reference to Fig. 4 that those portions of the blank'which are to,

form the corner portions of the finished box arecut away, as indicated at 9 in Fig. 4, so

as to prevent'excess of metal at the corners.

The upward bulges or swells at the corners provide more or less flexible portions which will take up the expansion and contraction of the box in use, and prevent its giving way as a'result of strains due to expansion and contraction. The bulges also permit the box to I be more readily placed in position over a' pile of plates or sheets) The bulged corner portions also provide for taking up the excess of metal at the corners, as otherwise in forming a box'with corners from a single plate or sheet, the metal would necessarily be lapped or folded at the corners.

My invention provides a one-piece box which is entirely free from joints and scams and which is much lighter and less likely to become broken or cracked in servicethan the usual cast box. There are no rivets or 7 other weak points to give way in service, and all sharp corners or angles are avoided.

I claim:

1; The herein-described method of making annealing boxes, which consists in providing an integral sheet metal blank, shaping said blank to give it an oval shallow box form, then reducing the transverse dimensions of such form to give a generally rectangular form to the box, and at the same time gradually deepening the box, and in said operations permitting the excess metal to form outward swells or bulges at the vertical corners of the box, substantially as described. Y

2. The herein-described method of making annealing boxes, which consists in providing a sheet metal blank of generally rectangular form with its corner portions cut away, subjecting said blank to a series of die forming 7 form, its and end walls are then contracted to give a generally rectangular form, and the depth of the box gradually increased, and in said operations permitting the excessmetal to form outward swells or blank having the corner portions thereof cut away, shaping said blank to give it an "initialoval shallow boxlike form, then rea C ducing the transverse dimensions of said form to give a generally rectangular shape to the box and at the same time gradually deepening the box, and in said operations permitting the excess metal resulting from the reduction of the transverse dimensions to form outward swells or bulges at the vertical cornersof the box, and retaining such swells or bulges in the finished article, sub stantially as described.

In testimony whereof, I have hereunto set my hand.

LUTHER L. KNOX.

Witnesses: W. O. LYON, H. M. OoRWIN.

c0515 this patent in, he obtained for five cents each, by addressing the "Commissioner of latent, r v I 'washingtomnc. I a 

